Adjustable drill sharpening guide



March 9, 1965 F. F. WOOD ADJUSTABLE DRILL SHARPENING GUIDE 2 Sheets-Sheet 1 PA RKER F.WOOD

IMAM A tmm ma A TTORNEY LL E INVENTOR.

March 9, 1965 P. F. WOOD 3,172,242

ADJUSTABLE DRILL SHARPENING GUIDE Filed Jan. 15, 1963 2 Sheets-Sheet 2 INVENTOR. PARKER F. WOOD WWW ATTORNEY United States Patent 3,172,242 ADJUSTABLE DRILL SHARPENING GUIDE Parker F. Wood, 845 Belle Ave., San Rafael, Calif. Filed lien. 15, 1963, Ser. No. 251,689 6 Claims. (Cl. 51-239) This invention relates to a twist drill sharpening device. More particularly, this invention relates to an adjustable guide for holding the drill during sharpening procedures.

The small home shop owner or hobby shop generally includes a grinding wheel and a minimum amount of other equipment. Thus, the hobbyist is at a loss to accurately sharpen his twist drills when they are worn. Some of the more sophisticated and highly advanced drill Sharpeners, which are presently in use, are much too complex and expensive to use considering how infrequently a hobbyist needs to sharpen his drill bits. If instead of using a sharpener for grinding drills, the hobbyist tries to sharpen his bits by hand holding them against the grinding wheel, the chances of his acquiring the proper angles and shapes are very unlikely.

Accordingly, it is an object of this invention to provide a simple, adjustable drill guide which can be easily built by the hobbyist or which can be inexpensively built by others.

A more specific object of this invention is to provide an adjustable drill guide assembly which is removably supported adjacent the side of a grinding wheel and adjustably oriented at proper angles to maintain the drill at the appropriate position for sharpening.

Another object of this invention is to provide an adjustable drill guide in which a rotatable turret having a plurality of drill receiving apertures is mounted to be pivoted about a first substantially horizontal axis and a second substantially vertical aris so that the drill bit inserted through one of the drill receiving apertures can be oriented in the proper angle for drilling. Once the proper orientation for the drill is set, locking screws are tightened to hold the structure at that angular orientation and that height.

A feature and advantage of this invention resides in the fact that once the drill guide is supported adjacent the grinder wheel, it can be properly oriented by means of two simple adjustments and thereafter removed or replaced from the position adjacent the drill without touching or changing the adjusted settings. Thus, the operator can initially set the drill guide and thereafter remove it and place it on a shelf or out of the way when he wishes to use the grinding wheel alone. At such times as when the hobbyist wishes to use the drill guide, he can merely drop it or place it in the support structure without adjustment. In addition, when surface conditions of the grinding wheels so dictate, the guide can be raised or lowered on the support.

Still another object of this invention is to provide a drill guide of the above type in which a rotatable turret having a plurality of drill receiving guide holes formed in it is rotatably mounted to expose different ones of the drill receiving apertures so that a twist drill can be inserted therethrough and held against the side of the grinding wheel for sharpening procedures, the turret being held in place by a plurality of detents formed on one face which coact with a detent pin to hold the drill receiving apertures in position during the sharpening procedures.

An advantage of this resides in the fact that the different sized drill receiving apertures can be positioned and held in place by a reciprocally mounted detent pin so that the drill receiving aperture is non-movably held in position during the sharpening or grinding procedures.

Other objects, features, and advantages of this invention will become apparent upon reading the following 3,172,242 Patented Mar. 9, 1965 detailed description and referring to the accompanying drawings in which:

FIGURE 1 is a rear elevational view of the drill sharpening guide;

FIGURE 1:: is a side elevational view of a lock washer which is normally located between the tilt bar and the swinging bar to hold or secure the drill sharpening guide at a proper elevational angle;

FIGURE 2 is a side elevational view of the drill sharpening guide of this invention showing a pin vice adapted to hold a twist drill during the sharpening procedures;

FiGURE 2a is a side elevational view of the detent pin which is normally reciprocally mounted to hold the drill guide turret in position;

FIGURE 3 is a plan view of a horizontal angle scale which is used between the side face of the grinding wheel and the front face of the drill guide turret to set the drill guide at the proper angle for grinding;

FIGURE 4a is a front elevational view of the tilt bar with the turret removed;

FIGURE 4b is a side elevational View of the tilt bar of FIGURE 4a showing the elevation angle pointer;

FIGURE 40 is a top plan view of the swing bar;

FIGURE 40. is a side elevational view of the swing bar showing the attached elevation angle scale;

FIGURE 5 is a partial top plan view showing the turret and pin vice in relation to the grinding wheel; and

FIGURE 6 is a side elevational view of FIGURE 5.

In this invention there is provided generally a support shaft 2 which is adapted to be inserted in shaft receiving member in base plate 1. A pair of adjacent arm or bar members 4 and 5 are interconnected and slidably mounted on the shaft 2 such that vertical and horizontal axes of movement are provided. Tilt bar 4 is pivotally connected to one side of swinging or pivot arm 5 such that its longitudinal axis can be inclined upward or downward. Pivot bar 5 is, in turn, positioned and connected to be pivoted about support shaft 2 and locked in position at any desired horizontal angle. The rotating turret 3 is in turn pivotally connected to the front end of the tilt bar or arm 4 such that the axes of individual drill receiving apertures are oriented at a certain or predetermined elevational angle and horizontal angle. In order to secure the turret in position a reciprocally mounted detent pin 9 is connected to cooperate with the detent holes in the rear face of the turret. Once the appropriate angles are set, a twist drill can be inserted through a drill receiving aperture and rotated against the side face of a grinding wheel 15 by means of a pin vice 10.

Now referring to the details of the drill sharpening guide, FIGURE 1 shows a base plate 1 having a hollow support shaft receiving hub projecting upward therefrom. Thus, as support shaft 2 is inserted into the hub of the base portion 1, the two shaft ears are received by hub detents to hold the shaft against vertical and rotational movement. Although substantial structure has been shown for the hub of base 1, it should be noted that other structures could be used which would be flush with the surface of the base thereby providing a permanent work surface on the grinding wheel which will not affect grinding work at times when the drill guide is removed. About the only requirements are that an aperture be formed and a pair of radially extending ear receiving detents provided so that the support shaft 2 can be securely held in place.

In order to properly sharpen a twist drill, it is necessary to provide a structure which allows the drill axis to be oriented in a combination of vertical and horizontal angles. Thus, the swinging or pivot bar 5 is slidably connected to the support shaft 2 and adapted to be raised,

e3 lowered, and pivoted about the shaft axis. In order to mount the swinging bar on the support shaft the keyhole aperture is dimensioned to a tolerance slightly greater than the diameter of the support shaft. Once swinging bar 5 is mounted on the support shaft 2, the thumb screw 8 is tightened causing the slot portion to come together thereby effectively decreasing the diameter of the aperture. As a result, swinging bar 5 is locked in place on the shaft. Conversely, when it is desired to reorient the swinging bar or arm 5, thumb screw 8 is loosened to effectively increase the diameter of the aperture thereby permitting rotational. and vertical movement between support shaft 2 and swinging bar 5. Thus the cooperative relationship between swinging bar 5 and support shaft 2 permits a raising and lowering of the height of the drill guide and a pivoting of the guide about any horizontal angle.

In that the usual twist drill also has a slight rake angle in the tip it is necessary to also orient the drill at a second angle hereinafter referred to as the elevational angle. In order to accomplish this adjustment, a tilt bar or tilt arm 4 is pivotally connected to a side wall of swinging bar 5. This tilt bar 4 has an aperture extending through it transversely to the keyhole aperture so that tilt bar thumb screw 7 can operate as the horizontal axle. Thus, when tilt thumb screw 7 is screwed into the body portion of swing bar 5, the lock washer 6, which is sandwiched between the side walls of the bars 4 and 5 is clamped thereby holding the axis of tilt bar 4 at an elevational angle to swinging bar 5. Conversely, loosening the thumb screw 7 permits an operator to change the elevational angle.

The front end of tilt bar 4 has an apertured turret 3 rotatably mounted on an axle hub by means of a bolt or other conventional fasteners. This turret has a. plurality of drill receiving apertures of progressively increasing sizes formed through it which operate to hold the drill in place during grinding, as will be explained shortly. This turret 3 has a radius suflicient to maintain the drill guide apertures sutficiently far above the top of the tiltbar 4 so that the chuck portion of pin vice It) will not be obstructed when used to insert a drill through an aperture. In addition, the thickness of turret 3 should be sufficient to provide a substantial support area to prevent axial wobble of the drill bit during grinding operations.

In order to hold the aperture chuck in place after the desired drill guide apertures are rotated into position, a detent pin 9 is reciprocally mounted in the lower body portion of tilt bar 4 so that the tip of the detent pin will cooperate with tie detent holes formed in the rear face of turret 3. When it is necessary to rotate turret 3, the knurled knob of detent pin 9 is pulled to withdraw the tip thereof from the detent hole thereby allowing the turret to be rotated. When the proper drill guide aperture is in place the detent pin is released and the spring force reciprocally drives the tip of pin 9 into the appropriate detent slot to lock the turret in place.

An elevational angle gauge or scale 13 and pointer 12 are provided at the rear of the guide assembly bars. The scale 13 is secured to the side wall of swinging bar 5 and as a result always maintains the same horizontal relationship with grinder base 1. The pointer 12.is, however, secured to a wall tilt bar 4 and moves relative to the elevational scale when the tilt bar is tilted. In order to determine when the proper rake angles are obtained, the scale 13 is. calibrated with angle marks such as 12 and as illustrated in FIGURE 4d.

There is, however, no horizontal angle scale permanently attached to the guide assembly. A hand scale 14 is provided for this purpose. In order to set the horizontal angle it is necessary to place the front face of rotatable turret 3 against horizontal scale 14 such as shown in FIGURE 3 with the other edge of the scale 14 against the side of grinding Wheel 15. This horizontal angle setting is shown more clearly by the top view of FIGURE 5.

As illustrated in turn by FIGURE 6, the side elevational view shows how the tilt bar would hold the drill at a 15 vertical angle. Of course, it should be understood that 12 could also be used.

Now referring to the operation of the device, it is seen that when the appropriate altitude or height is selected on the support shaft 2, the assembly can be pivoted through horizontal angles so that the edges of horizontal scale 14 rest simultaneously on the side edge of grinding wheel 15 and the front face of rotatable turret 3. Thereafter, the thumb screw 8 is turned down to lock the as.- sembly at the proper horizontal angle of say, for instance, 31. Then the tilt bar or arm 4 is tilted upward until the tip of pointer 12 is on either the 12 or 1S" mark, depending upon which angle is selected. Thereafter, the tilt bar thumb screw 7 is tightened down to lock the guide assembly at the appropriate incline or elevational angle. As a result, the drill guide apertures are oriented at a 31 horizontal angle and at either a 12 or 15 vertical angle which results in guiding the drill top at the appropriate or proper angle for grinding.

Once the guide assembly is set up, the pin vice 1t), having a pointer 11, is moved into coaxial alignment with the appropriate drill guide aperture and inserted therethrough to bring the tip of the drill into contact with the side of grinding wheel 15. Thereafter, the pin vice 10 is rotated through a predetermined angle to dress the tip of the drill.

For some reason it may also be necessary to adjust the height 'of' the guide assembly on support shaft 2. This can also be done by loosening thumb. screw 8 and raising or lowering the device accordingly.

Thus, there is provided a simple drill guide device which has. a few parts which cooperate to provide the appropriate angles for drill sharpening.

Although one embodiment of this invention has been illustrated for purposes of description it should be understood that other changes could be made in the shapes of the parts and materials used without departing from the scope of the invention as defined in the following claims.

I claim:

1. A drill guide assembly of the type which can be mounted adjacent a grinding Wheel comprising: a support member including a base and a vertical shaft mounted on said base perpendicular thereto, said shaft being mounted in substantially non-moveable relationship to said base; horizontal angle adjusting means connected to said shaft for relative horizontal rotation therewith and for sliding movement therealong; first locking means mechanically connected to said shaft and to said horizontal angle adjusting means to secure said horizontal angle adjusting means at predetermined angles with respect to the axis of said shaft; elevational angle adjusting means rotatably connected to said horizontal angle adjusting means for rotation in a relatively vertical plane; second locking means mechanically connected to said horizontal and elevational angle adjusting means to secure both of said angle adjusting means against movement relative to one another; and an apertured drill guide. member connected to said elevational angle adjusting means for guiding a drill against said grinding wheel at a position having vertical and horizontal angles with respect to the longitudinal axis of said shaft, and at a desired height with respect to said base determined by the positions of said horizontal and elevational angle adjusting means respectively.

2. Thedrill guide assembly of claim 1 in which the drill guide member is rotatably mounted about the axis of said elevational angle adjusting member at a vertical angle with respect to the longitudinal axis of said shaft, and wherein said drill guide member includes a plurality of spaced apertures each of a different size whereby drills of various sizes are operably guided against the grinding wheel through these apertures.

3. The drill guide assembly of claim 2 in which said rotatably mounted drill guide member includes a plu- 3 rality of detent holes formed on one face thereof and including a detent pin reciprocally mounted to said elevational angle adjusting member for cooperation with said detent holes whereby said drill guide member is operably locked in place when the detent pin is received by the detent slot.

4. The drill guide assembly of claim 3 in which said horizontal angle adjusting member is mounted on said shaft by a keyhole aperture, wherein said first locking means includes a screw member operably connected through said aperture to effectively decrease the aperture diameter to secure said horizontal angle adjusting member and said shaft against relative rotation; and said elevational angle adjusting member is rotatably secured to said horizontal angle adjusting member by a screw member, said screw member being operably connected to bias both said members into functional cooperation to prevent rotation relative to one another.

5. The drill guide of claim 1 including an angle scale secured to said horizontal angle adjusting means and a pointer secured to said elevational angle adjusting means, said pointer being positioned adjacent the face of said angle scale for relative movement t'uereacross whereby the elevational angle of the drill guide can be accurately adjusted.

6. A drill guide assembly for mounting in fixed space relation to a grinding wheel comprising in combination: a base, a shaft mounted on said base, means mechanically connected to said base and to said shaft to secure said shaft with respect to said base, a drill guide member formed with at least one aperture of a desired diameter to guide a drill for axial movement toward and away from said grinding wheel, and drill guide mounting means for adjustably mounting said drill guide member to said shaft, said drill guide mounting means including a first member mounted on said shaft for sliding movement therealong, means for releasably locking said first member at a desired position along said shaft, means mounting said drill guide member to said first member for affording rotative movement of said drill guide member with respect to said first member about an axis parallelly spaced from the axis of said drill guide aperture, and means for engaging said rotative movement affording means to position said aperture at a desired rotative position.

References Cited by the Examiner UNITED STATES PATENTS 1,231,258 6/17 Horvath 5l--2l9 2,583,159 1/52 Swanson 512l9 2,701,432 2/55 Kent 51217 2,848,847 8/58 Casselman 5 l219 3,057,122 10/62 HeWes et al. 51125 LESTER M. SWINGLE, Primary Examiner.

JOHN C. CHRISTIE, Examiner. 

1. A DRILL GUIDE ASSEMBLY OF THE TYPE WHICH CAN BE MOUNTED ADJACENT A GRINDING WHEEL COMPRISING: A SUPPORT MEMBER INCLUDING A BASE AND A VERTICAL SHAFT MOUNTED ON SAID BASE PERPENDICULAR THERETO, SAID SHAFT BEING MOUNTED IN SUBTANTIALLY NON-MOVEABLE RELATIONSHIP TO SAID BASE; HORIZONTAL ANGLE ADJUSTING MEANS CONNECTED TO SAID SHAFT FOR RELATIVE HORIZONTAL ROTATION THEREWITH AND FOR SLIDING MOVEMENT THEREALONG; FIRST LOCKING MEANS MECHANICALLY CONNECTED TO SAID SHAFT AND TO SAID HORIZONTAL ANGLE ADJUSTING MEANS TO SECURE SAID HORIZONTAL ANGLE ADJUSTING MEANS AT PREDETERMINED ANGLES WITH RESPECT TO THE AXIS OF SAID SHAFT; ELEVATIONAL ANGLE ADJUSTING MEANS ROTATABLY CONNECTED TO SAID HORIZONTAL ANGLE ADJUSTING MEANS FOR ROTATION IN A RELATIVELY VERTICAL PLANE; SECOND LOCKING MEANS MECHANICALLY CONNECTED TO SAID HORIZONTAL AND ELEVATIONAL ANGLE ADJUSTING MEANS TO SECURE BOTH OF SAID ANGLE ADJUSTING MEANS AGAINST MOVEMENT RELATIVE TO ONE ANOTHER; AND AN APERTURED DRILL GUIDE MEMBER CONNECTED TO SAID ELEVATIONAL ANGLE ADJUSTING MEANS FOR GUIDING A DRILL AGAINST SAID GRINDING WHEEL AT A POSITION HAVING VERTICAL AND HORIZONTAL ANGLES WITH RESPECT TO THE LONGITUDINAL AXIS OF SAID SHAFT, AND AT A DESIRED HEIGHT WITH RESPECT TO SAID BASE DETERMINED BY THE POSITIONS OF SAID HORIZONTAL AND ELEVATIONAL ANGLE ADJUSTING MEANS RESPECTIVELY. 